Preview error

We have an issue with our latest file addition – the file uploads to the server fine, but when viewing on the front of the website we get this error:

PDF.js v1.9.426 (build: 2558a58d)
Message: Unexpected server response (0) while retrieving PDF “https://xxxxxxx.co.nz/?wpdmdl=7277&ind=0&open=1”.

Downloading this receives a “Failed – Network Error”

Other file downloads loaded previously are working fine

Thanks

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